Refrigerating apparatus.



E. C. LOETSCHER.

REFRIGERATING APPARATUS.

APPLICATION FILED IIIAR. 24. I9I5.

WITNESSES.-

EMIL C. LOETSCHER, F DUBUQUE, IOWA.

nnrnicnna'rme APPARATUS.

Specification of Letters Patent.

Patented Apr., 241i, 1191i '2'.

Application led March 24, 1915. Serial No. 16,551.

To all whom t may concern:

Be it known that L EMIL C. Lonrscnnn, a citizen of the United States,residing at Dubuque, in the county of Dubuque and State of lowa, haveinvented certain new and useful Improvements in Refrigerating Apparatuslof which the following is a speciiication.

The principal object of my invention is to provide an automatic controlin refrigerating apparatus of the character described whereby theheating agent may be alternately applied and cut oft' during each cycleof operation.

Another object of the invention is to provide automatic means wherebythe process of absorption is terminated at a predetermined point in thecycle of operation in order that the eiiectiveness of the machine is notimpaired by the absorption process continuing beyond a certain point.

Still another object of the invention resides in providing automaticmeans entering into the control of the apparatus and y operated by thetemperature in the refrigerator member whereby the temperature in therefrigerator will not rise above a certain predetermined point.

invention further resides in the conjoint operation .of the individualcontrolling means whereby the eillciency and effectiveness of theapparatus is materially increased over apparatuses of similar character.

Haring now described the broad objects of my invention, I will proceedto point out the mechanism by means of which the broad objects of myinvention are accomplished.

Figure 1 is a side elevational view of my improved refrigeratingapparatus with parts in section. I

Fig. 2 is a side elevational view of the gas valve plunger.

Fig. 3 is a longitudinal sectional view of onerof the thermostaticmembers.'`

Fig. 4 is a sectional view of the line 4 4 of Fig. 3.

Fig. 5 is an end view of Fi 3.

Fig. 6 is a sectional view cfg the gas valve.

Referring now more particularly to the drawing, the generator-absorber10 is of the ,Y

horizontal type and is provided with a'vapor conveying member 11. whichextends up- 'ftardly from the generatonabsorber and is tiien bent uponitself with its discharge end entering the equalizing member l2.

An absorption pipe 13 disposed near the bottom of the generator-absorberis connected to the equalizing member by the eXtension pipe 14, theupper end of the extension pipe 14 projects beyond thevlower end of thevapor conveying member 11 so as to form an overflow pipe for the liquidin the equalizing member; the normal level of the liquid being indicatedat B and which pipe maintains a uniform height of liquid within theequalizing member.

A rectifying coil 15 has one end in com munidation with the equalizingchamber 12 with the coils thereof located within a condensing tank 16.

Within the generator-absorber is a cooling coil 17 to the upper end ofwhich is connected an elbow 18 which enters the condensing tank and theupper end 19 of which is located at a point slightly below the highestoverow level indicated at 19A of the condensing tank. A check valve 20is preferably located in the pipe 17 to prevent return How to thecondensing tank. A cooling medium7 such as water, is supplied to tank 1Gby means of a water supply pipe 16A prelferably discharging at thebottom of the tan The condensing chamber 21 is constructed preferably ofa seamless shell provided with a single inlet and outlet communicatingmember 22 terminating at the bottom of the condensing chamber 21 andprovided with a plurality of perforations 23. The refrigerating member24 consists essentially of a seamless receiving vessel 25 to which arefrigerating coil 26 is connected having both of its ends incommunication with the chamber 2li. Surrounding the receiving vessel 25is insulating material 27 which material is held in place by a jacket28.

A brine tank 29 is located within the ice chamber 30 of an ordinaryrefrigerator 31 and the refrigerating coil 26 is located Within thebrine tank 29. Within the receiving vessel 25 is an enlarged pipe32surrounding one of the terminal ends of the coil 26 andterminatingbelow the top of the vessel 25.

The pipe 33 or refrigerant conveyingmember which is incommunication withthe rectitying coil 15 has one of its ends passing through the receivingvessel 25 and into the enlarged pipe 32 discharging at a oint near theupper end ot said pipe 32. suitable fork 42 on the arm 41. The disk 56is pref-V valve 34 is employed for the purpose of charging the apparatuswith the refrigerating solution.

Within the generator-absorber 10 is a thermostatic member 35, shown indetail in Figs. 3,' 4 and 5.o This thermostat consists of a shell 36within which is a shell 37 provided with bearing head` 38 for supportingthe shaft 39. The inner end of the shaft 39 carries a spiral member 40which is preferably a strip of thermostatic material consisting of twometals having different coefficients of expansion. One end of thethermostatic metal is fastened to the shell 36 and the other end to theshaft 39 whereby a rise in temperature will cause the shaft 39 to rotatein one direction and a fall in temperature will cause a reverserotation.

An arm 41 is secured to the shaft 39 but insulated therefrom and isprovided with a forked end 42. A gas valve 43, shown in detail in Fig.6, is connected to the gas supply pipe 44 and has a gas outlet pipe 45also connected thereto. f

A diaphragm 46 is suitably mounted within the valve which diaphragmcarries a valve seat 47 coperating with the seat 48 formed integral withthe valve casing.

A spring 49 normally holds the valve open by forcing the diaphragmupward. A plunger 50 has its lower end in contact with the diaphragm andits upper end projecting beyond the valve casing. A solenoid magnet 51is mounted directly over the center of the plunger 50 of the gas valve43 and in axial alinement therewith. The plunger 52 of the Solenoid isprovided with a groove 53 into which groove a locking pin 54 is adaptedto project for locking the plunger 52 in its upper osition.

The loc 'ng pin 54 is suitably mounted in bearing blocks 55 attached toany convenient point upon 'the frame of the machine, whereby the lockingpin is held in proper relation to the plunger 52 and arm 41.

AMounted upon the locking pin 54 are two disks 56 and 57, upon oppositesides of the erably made of insulating material such as fiber and isprovided with a metal disk 58 secured thereto but insulated from thelocking pin 54. Disk 57 is made of liber or other insulating material.

A spring 59 holds the locking in in engagement with the lunger 52 andalso forces disk 58 away rom Contact point 60 for a purpose to behereinafter described. The plunger 52 of the solenoid extends throughthe winding and is provided with an extension 61 to which a weight 62 isattached.

A supporting bracket 63 is suitably connected to the frame and has alever 64 connected to it at its upper end. One end of the lever ispivotally connected to the weight fitting 67 leading to the trap 68 andfrom the trap to the sewer through the pipe 69.

Referring now to the re rigerating member designated as 24, an extensiontube 70 is suitably secured to the shell 25 and is provided with anelbow or extension 71 around which are one or more convolutions of athermostatic metal 72 which thermostatic metal is electrically insulatedfrom the elbow 71. Within the tube 70 is a circulating tube 73 providedwith a funnel shaped opeirrg 74, the funnel end of which terminateswithin the chamber 24 and its other end at the closed end of the tube70. The function of vthe tubes 70 and 73 is to maintain a circulation ofthe refrigerant within both of said tubes until all of the liquid in thechamber 24 has been evaporated. The cone 74 traps some of the gaseousrefrigerant and thus forces some of the liquid refrigerant contained inthe tube 73 against the force of gravity into the tube 70 and extension71 where it evaporates causing the thermostat to deflect due to thelowering, of temperature produced by the evaporatlng refrigerant.Another thermostat 75 is placed within the refrigerator. This thermostatcomprises a section of thermostatic metal 76 and a contact screw 77 toopen and close the electric circuit at a predetermined temperature. rlhethree thermostatic members, namely, 35, 72 and 75 are connected inseries'shown by wires 78, 79, 80 and 81 to a battery or other source ofelectrical energy 82. The winding of the solenoid 51 is also connectedin series with` the thermostats.

A gas supply pipe 44 leads to the gas valve 43 and the gas outlet pipe45 has a burner 83 that is located below the generator-absorber. Aby-pass pipe 84 serves to keep the pilot light burning whenever themainv burner is shut oil'.

The operation of the machine will now be described in detail. Assumingthat the generator-absorber 10 has been charged with a suitable quantityof a refrigerating`medium, such as aqua ammonia of suitable strength, tothe level indicated at (a) Fig. 1, and that the chamber 12 has beenfilled to the level indicated at (b), Fig. 1, by means of the chargingvalve 34. And it being further assumed that the pilot light at the endof the pipe 84 has been lighted and that the cooling mediumhas filledthe condensing Laaaeis tank 16 and also that the battery 82 has beenconnected as indicated, and all the thermostats 35, 72 and 75 have beenproperly adjusted. The electrical energy from the battery 82 will nowflow through the solenoid 51 moving the plunger 52 upwardly therebyopening the valve and allowing the gas in the pipe 44 to flow to theburner 83. The upward movement of the plunger 52 simultaneously lowersthe sleeve 35 to the position shown in Fig. 1, which lowers the level ofthe liquid in the condensing tank 16 to the lower level as indicatedupon the drawing. rlhus the water in the condensing tank 16 cannot passinto the intake end 19 of the pipe 18 as the water will flow over theupper end of the sleeve 65 and into the pipe 66. When thegenerator-absorber 10 becomes heated the aseous vapor arising from theliquid thereln passes through the pipe 11 and bubbles up through theliquid surrounding the discharge end of said pipe. A small quantity ofliquid is carried through the pipe 11 with the vapor which maintains theliquid level in the chamber 12 and any excess liquid flows back into thegenerator-absorber through the pipe 14. lt is essential that the liquidlevel in the chamber 12 be maintained as will later appear.

The pipe 11 serves to equalize the pressure in the generator-absorber10, and the chamber 12, except for theyery slight liquid pressurewhichmust be overcome due to the pipe 11 dipping into the liquid in thechamber 12. The tendency of the liquid in the generator to be forced upinto the pipe 14 and thence into the chamber 12 and subsequently intothe rectifying coil 15 is thus entirely overcome owing to the pressureequalizing action of the tube 11. The vapor now passes through therectifying coil 15 at which point any entrained water vapor iscondensed. rllhe water resulting from this condensation flows back intothe chamber 12 and thus further serves to maintain the liquid leveltherein and automatically supplying any loss by evaporation.

The gaseous vapor, now free from water,

passes through valve 34 and pipe 33 into the4 refrigerating chamber 24wherein it generates a pressure not only in the chamber 24 but in thecoil 26 as well. vapor next passes through the pipe 22 and out throughthe openings 23 intothe condensing c-hamber 21. As ythe solution in thegenerator-absorber becomes weaker its temperature gradually risesy andasa consequence the arm 41 slowly moves to the right as indicated bythe. dotted lines. The forked end 42 of thearm`41 vnowengages disk 57moving the locking pin 54 whereupon the plunger 52 drops by gravity uponthe plunger 50 of the gas valve.k The vdisk 57 is set at a point wherebythe arm 41 will not come rThe gaseous in contact with the same until thesolution in the generator-absorber has been weakened to a predeterminedpoint as indicated by its temperature. As the plunger 52 falls upon theplunger 50 the gas valve is closed and at the same time sleeve 65 israised which in turn raises the overflow level in the condensing tank 16to the level indicated at 19a. As al result the water now flows throughthe pipe 18 to the coil 17 which is positioned within thegeneratorabsorber, thus cooling the liquid within the generator andcausing a reduction of pressure therein. rlhe same reduction in pressuretakes place in the chamber 12 and in the refrigerating chamber 24. Asthe pressure in the generator-absorber is reduced the liquid in thechamber 12 is forced up pipe 11 to the point indicated at (c) which willbe suliciently high to force the returning gas into pipe 14 and throughthe perforations in the absorption pipe 13 causing the returning gas tobe absorbed by the liquid-in the generator-absorber.

When the pressure in the generator-absorber has been reducedsufiiciently, the pressure existing over the liquid anhydrous ammonia inthe condensing chamber 21 will cause it tolow upward out of thecondenser against gravity through the pipe 22 and to be deposited in thechamber 24 and coil 26 filling said chamber 24 to a level as indicatedat (d). Afurther reduction in pressure causes the ammonia in chamber 24and coil 26 to evaporate lowering its temperature and producing thedesired refrigeration within the chamber 30 of the refrigerator.

As the temperature within the generatorabsorber is lowered, thethermostat designated as a whole at 35 and located within thegenerator-absorber, will cause the arm 41 to move toward the left untilit contacts with the disk 58. This disk has previously been brought intocontact with contact point 60 and is heldin such contact by the fallingof plunger 52 which thus lprevents locking pin 54 from moving to the,left until they plunger 52 is raised. The contacting of arm 41 with thedisk 5.8, which closes .the circuit through v'the solenoid, willA notycause the electrical energy to :dow through it unless the otherthermostat 72 and 75. are also closed.

,During the interval'that the arm 41 has been moved tothe left,thermostat 72 keeps the circuit open' for the lowered temperatureproduced in theextension arm 71 causes thermostat 72 ,to recede' from`its contact point 71a, thusypreventingthe actuation of 'the solenoid.Iy

The extension tube will remain cold as long as there is any liquidammonia to be 'evaporated thereinl. lin order to keep the extension tube70 cold until all the ammonia within the chamber 24 has evaporated, l

. soon as the plunger 52 risesi, the lockin employ the circulating tube73, which is provided with an inverted funnel end 74 to ele vate theammonia liquid by means of its own evaporation.

It is desirable, however, to terminate the process of evaporation orcooling lwhen the coil 26 of the refrigerating member is substantiallyfull of liquid. Under such conditions the coil 26 cannot act as acondensing coil while the generating process is going on. Whatevercondensation might take place in the coil when it is emptied during eachcycle would warm up the surrounding brine, thus counteracting thepreviously produced refrigerating effect and appreciably lowering theeiciency of the apparatus.

Assuming now that all of the ammonia in the chamber 24 has beenevaporated and that the extension tube begins to thaw or warm up due tothe temperature of the surrounding air, the thermostat 72 moves intocontact with contact point 71a. The solenoid 51 still will not beenergized until the thermostat 75 is also closed, which will bethe caseif such thermostat is set to open at a lower temperature than theltemperature of the chamber in which it is located. If, however, thetemperature of the chamber 30 is lower than the desired temperature forwhich the thermostat is set, the latter will hold the circuit open untilthe temperature within the chamber 30 rises to the predetermined pointat which the thermostat is set.

When the circuit is closed by the thermostatic metal 76 coming incontact with contact point 77, al1 contacts are thus closed and theelectrical energy from the battery 82 now flows through the solenoid 51,causing plunger 52 to rise. As soon as plunger 50 is relieved of thepressure from plunger 52, the diaphragm 46 is moved upwardly by thespring 49, thus opening the gas valve and a new cycle of operation isstarted. As 1n 54 is forced into the groove 53 thus ho ding the plunger52 away from the plunger 50 and keeping the gas valve open. With themovement of the locking pin 54 to the left, the electricall circuit isbroken at contact point 60, thus denergizing-the Asolenoid 51 andrelieving the battery. It will be seen that the current is thus ofmomentary duration and may be readily supplied by ordinary dry cells.

It is evident from the above description that I have provided meanswhereby a given temperature is maintained in the refrigerator and inaddition to this salient feature lI have provided means whereby thecycle .ofabsorption may. be begun and also maybe terminated at apredetermined point,r

both of which are essential to an automatic machine of this character.

It sometimes happens that a small quantity of water may be carried overwith the ammonia gas from the rectifier to the condenser thus loweringthequality of the ammonia and impairing. the eliiciency of theapparatus. I have provided simple automatic means for removing any suchwater as follows:

When the machine is operating normally the anhydrous ammonia from thecondenser will fill the chamber 24 to the level indicated at (d).Assuming now, that for some reason, in case there is too small aquantity of cooling water lover the rectifier, a small quantity ofaqueous vapor passes over with the ammonia to the condenser. When 'thisammonia is transferred to the chamber 24 the latter will be filled tothe level indicated at (e). Assuming also, that the previous operationhad likewise carried over a slight quantity of water, it is obvious,that when the evaporation is terminated, a comparatively largepercentage ofy water will be contained in the liquid remaining in coil26, which would continually increase until apparatus if not removed. Thefresh charge of nearly anhydrous ammonia coming from the condenserthrough pipe 22-will bedeposited in chamber 24 and thus forcepractically all of the liquid in the coil 26 downward and then upwardinto tube 32, until the level has been reached in chamber 24 and in tube32. Inasmuch as thel liquid cannot get out through tube 22 and as itsonly exit is through tube 33 and thence 'through the rectifier back tothe generatorabsorber, it is clear that by varying the size of tube 32,and the location of the end of tube 33, any predetermined amount ofwatery ammonia may be removed from the refrigerating member and returnedto the generator-absorber, even against the force of gravity.

Having now described my invention in detail, I will proceed to point outthe novel features which I claim as my invention.

I claim- 1. In refrigerating apparatus of the absorption type, thecombination therewith of y 'thermostatio means and operated by thetemperature of said refrigerating member.

3. yIn refrigerating apparatus of the absorption type comprising agenerator, an absorber, a condenser and a refrigerating member, thecombination therewith of means for heating said generator, thermostaticmeans for controlling the heating agent operated by the temperature ofsaid generator and thermostatic means for controlling the operation ofthe heating agent thermostatio means and operated by the temperature ofthe apparatus at a point near the refrigerating member.

4. In refrigerating apparatus of the absorption type comprising agenerator, an absorber, a condenser, a refrigerating member and arefrigerator, the Combination therewith of means for heating saidgenerator, thermostatio means for controlling the heating agent operatedby the temperature of said generator, thermostatic means for controllingthe operation of the heating agent thermostatic. means and operated bythe temperature of said refrigerating member and thermostatic means insaid refrigerator operated by the temperature therein and oontrollingthe operation of said heat controlling and refrgerating thermostaticmeans.

5. In refrigerating apparatus of the absorption 'type comprising agenerator, an absorber, a condenser, a refrigerating member and arefrigerator, the combination therewith of thermostatie means in saidgenerator, thermostatic means in said refrigerating member andthermostatio means in said refrigerator and means whereby the operationof theJ heat controlling thermostat in said generator is controlled bythe conjoint operation of the thermostats in said refrigerating memberand said refrigerator.

6. In refrigerating apparatus of the absorption type Comprising agenerator, an absorber, a condenser, a refrigerating member and arefrigerator, the Combination therewith of thermostatic means in saidgenerator, thermostatic means in said refrigerating member andthermostatio means in said refrigerator and means whereby the operationof the heat controlling thermostat in said generator is controlled bythe conjoint operation of the thermostats in said refrigerating memberand said refrigerator, said thermostats operating at differentintervals.

7. In refrigerating apparatus of the absorption type comprising agenerator, an absorber, a condenser, a Condensing'tank and arefrigerating member, of means for heating said generator, a heatcontrolling member and Water controlling means in said condenser tankactuated by said heat controlling member.

EMIL C. LOETSCHER.

Vitnesses:

R. W. JAMES BARNETT,

A. RYAN.

